The obvious place to look for the answer to this question is history. And the historical record shows
that the present forms are a result of gradual evolution over centuries. But their evolutionary route
was not at all uniform, or consistent. And while we would see that the number one, seven, and zero
show a remarkable consistency of form throughout the evolutionary period, we would at the same time
see little resemblance between the modern forms of the rest of the numbers and their ancestors.

Confusion abounds regarding the origin of the symbols. Several different and conflicting claims
are made; each with some justification. We call them "Arabic", or "Hindu-Arabic" numerals, which is
probably fitting since some of the symbols appear independently in India, Egypt, Persia, and Arabia.
It's probable that traders, needing most of all a practicable number system, carried the forms used in
their homelands along with the goods that they exchanged.

The question really becomes whether or not the numerals were consciously conceived and
designed in their present forms as one complete system. Or, whether they have evolved to their present
state of what certainly appears to be a very logical design scheme wholly by chance without any
conscious effort on the part of mankind. Certainly, the probabilities of "chance" being responsible rival
those of the monkey composing the works of Shakespeare. And if not the result of conscious efforts of
men, as the historical record would suggest, then must there not be some other explanation?